Project Summary With the near linear increase in life expectancy experienced by high-income countries, the question of whether the extra years of life are healthy or not is a key concern. This project will develop appropriate techniques to investigate the determinants of healthy life expectancy (HLE) and unhealthy life expectancy (ULE). We will then evaluate the individual and joint contributions of three behavioral factors?cigarette smoking, obesity, alcohol use?to HLE and ULE in the United States and Europe. We focus on the role of these three factors in determining levels of HLE and ULE within countries and their role in explaining differences across countries. A goal in the cross-national studies is to better understand the shortfall in U.S. health and longevity relative to other high- income countries. We further will identify the chronic diseases that are most important in mediating the relationship between behavioral factors and health expectancies (HLE and ULE). The methods that we employ and will disseminate can be used to study a wider set of determinants of HLE and ULE in future studies.